EagleMark
07-04-2011, 02:36 AM
Why is it I always find problems at 4500 RPM? This is not just one car or even one ECM. It has happened to me many times and I have read that I am not alone... example, car runs great and pulls like heck then at 4500 RPM it miss's, breaksup and continues or sometimes it just falls flat on it's face and stays there? I have fixed flat on it's face usually with a cap and rotor! Sometimes spark plugs and even a fuel filter.
There's got to be more to it than that. It's just to coincedental that it happens to many people. For me it has been a 1990 1227747 Suburban, a 1993 1228746 Caprice, and now a transplanted 5.7 TPI with a 1227730. I don't ever remember this happeneing back in the old days with carburators. I do remeber breaking up at high RPMs at the track with well built motors. But then it was closer to 6000 RPM? Beleive it or not we could not find a set of spark plugs that would not start to fail after 4 1/4 mile runs? Try to get a fifth run and the breakup would start again, sixth would be worse and by seven the breakup started to turn into a backfire as well...
There's got to be more to it than that. It's just to coincedental that it happens to many people. For me it has been a 1990 1227747 Suburban, a 1993 1228746 Caprice, and now a transplanted 5.7 TPI with a 1227730. I don't ever remember this happeneing back in the old days with carburators. I do remeber breaking up at high RPMs at the track with well built motors. But then it was closer to 6000 RPM? Beleive it or not we could not find a set of spark plugs that would not start to fail after 4 1/4 mile runs? Try to get a fifth run and the breakup would start again, sixth would be worse and by seven the breakup started to turn into a backfire as well...